Amortization Calculator
Generate a full amortization schedule showing every payment's principal, interest and remaining balance.
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Currency: Amounts are calculated in the currency you select; this site does not convert between currencies and does not use live exchange rates.
What this tool does
An amortization schedule is the loan's complete ledger: one row per payment showing how much went to interest, how much reduced the principal, and what balance remains. This calculator generates that schedule for any loan amount, rate and term, and surfaces the figure borrowers find most surprising — at the halfway point of a 30-year mortgage you still owe roughly three quarters of the original balance, because the early years are dominated by interest. Use the table to plan extra payments, check a lender's payoff quote, or see exactly when your equity crosses thresholds like 80% loan-to-value for PMI removal.
How to use the Amortization Calculator
- Enter the loan amount, annual rate and term in months.
- Read the monthly payment and lifetime interest totals.
- Scan the schedule table: each row is one month with payment, principal, interest and ending balance.
- Compare terms by re-running at 180 months to see the interest saved by a 15-year schedule.
Formula
Interest_m = Balance_(m−1) × r; Principal_m = M − Interest_m; Balance_m = Balance_(m−1) − Principal_m
- M
- Level monthly payment from the amortization formula
- r
- Monthly rate = annual rate ÷ 12
- Balance_m
- Balance remaining after month m
Payments are rounded to cents in the table; the final payment is adjusted so the balance ends at exactly zero, which is why the last row can differ by a few cents.
Worked example
A $250,000 loan at 6.5% over 360 months: payment $1,580.17, total interest about $318,861, and after 180 payments — halfway through the term — the balance is still about $181,398, roughly 73% of what was borrowed.
Inputs
- Loan amount$250000
- Annual interest rate (%)6.5 %
- Term (months)360
Result
- Monthly payment$1,580.17
- Total interest$318,861.22
- Total of all payments$568,861.22
- Balance at the halfway point$181,397.85
Results explained
- Monthly payment
- The constant payment applied in every row of the schedule.
- Total interest
- The sum of the interest column over the whole schedule.
- Total of all payments
- Principal plus total interest.
- Balance at the halfway point
- What you still owe after half the scheduled payments — usually far more than half the loan on long terms.
Frequently asked questions
A table of every loan payment split into principal and interest with the remaining balance. Lenders must be able to produce one for any amortizing loan, and it is the definitive record of how a loan pays down.
Because interest is charged on the balance, the principal slice starts small and grows. On a 30-year loan at 6.5% only about 27% of the principal is repaid in the first 15 years; the second half retires the other 73%.
When the balance falls below the point where monthly interest equals half the payment — on a 30-year 6.5% loan that crossover happens around month 233, well into the final third of the term.
Extra principal skips you ahead in the schedule: every extra dollar removes a dollar from the balance that would otherwise accrue interest for the remaining term. Model it with the Loan Extra Payment Payoff tool in this category.
No — during an interest-only period the balance never falls, so there is no amortization until the repayment period starts. See the Interest-Only Mortgage Calculator for that two-phase schedule.